Triassic-Jurassic Extinction Event

The Triassic-Jurassic extinction was the 4th of six mass extinctions on earth, as well as the least worst (6th worst). This happened 201-198 million years ago. This event was the least severe of the 6, although it is unknown why. It only wiped out 25-30% (maybe as high as 35%) of all life, marine and land. Many animals went unaffected, but some reptiles from the Permian and Early Triassic finally went extinct in this event, possibly the Dimetrodon went extinct here, but it is unclear if it did. This gave way for dominance of dinosaurs.